1. Field of the Invention
This invention relates to a camera of the kind incorporating a motor therein.
2.Description of the Related Art
Many of the cameras manufactured these days are arranged to automatically perform various operations such as film winding and rewinding, focusing, aperture operating and shutter charging actions with a motor power. The cameras of this kind are disclosed, for example, in U.S. Pats. No. 4,579,435, No. 4,673,272, No. 4,697,899, No. 4,816,851, etc.. In the case of the conventional manual operating type camera, these operations are serially and not simultaneously performed. Whereas, the latest motor-incorporating type cameras are arranged to permit high-speed photographing and quick preparatory actions by simultaneously performing at least two of the above-stated different actions, as disclosed in U.S. Pat. No. 4,659,201, etc.. Some of the latest cameras is provided with different motors specially for different operations respectively, as disclosed in U.S. Pat. No. 4,616,913, for carrying out the above-stated various actions at a high speed. The camera of that kind permits continuous photographing at such a high speed that has been hardly possible with the conventional camera.
The camera of the kind having at least two motors for automatic execution of film winding, film rewinding, focusing, aperture operating and shutter charging actions, etc. is capable of quickly carrying out photographing preparations and photographing. However, the camera necessitates the minimum operative voltage of a battery to be set at a high value, because several currents must be simultaneously allowed to flow to a plurality of motors. The battery, therefore, must be replaced when it still has an output voltage at a level high enough for a power supply to a single motor. This necessitates premature battery replacement and is, therefore, disadvantageous in terms of economy.
Many electronic circuits are included in the latest cameras and also in the camera accessories of varied kinds in many cases. A camera system having the electronic circuits mounted on both the camera and the accessory thereof is required to have not only perfect mechanical coupling but also perfect electrical connection between the camera and the accessory when the camera is used with the accessory mounted thereon.
The mechanical coupling of the camera with the accessory may be simply detected by the known detecting method of using a limit switch or the like which has been used for the conventional camera. However, the detecting method of using a limit switch or the like has been disadvantageous as the limit switch not only tends to malfunction but requires a space for setting it in addition to a space for electric circuit connection terminals. Besides, the conventional arrangement for detecting the mounted or coupled state by means of a limit switch is used for detecting the electrical connection of the accessory to the camera. It has been provided merely for electrical detection of a mechanical mounted state and not for detecting an electrically connected state. Further, since the electronic circuit is incapable of detecting the kind of the accessory mounted on the camera, another problem with the conventional arrangement is that the electronic circuit cannot be automatically set in accordance with the kind of the accessory.